It's a joke! It's a little smile in the day when you and co-worker are performing a Google search. Wisely, it is not the default behaviour, but providing the odd opportunity to divert for amusement's sake is a good way to enjoy popular power :-)

And if Google lose the plot, there'll always be another search engine to replace it. Teoma's cool. Daypop is fun. New look av.com not bad either.

We all know the general principles upon which Google's success is based. Another PageRankTM-alike (cough!) search algorithm shouldn't be hard to develop. Then it's just a matter of booking a few server farms and paying the phone bill.